Lycorine Induces Apoptosis and G1 Phase Arrest Through ROS/p38 MAPK Signaling Pathway in Human Osteosarcoma Cells In Vitro and In Vivo.

STUDY DESIGN: Xenograft osteosarcoma mouse model. OBJECTIVE: We determined the effect of lycorine on osteosarcoma. SUMMARY OF BACKGROUND DATA: Osteosarcoma is an aggressive malignant neoplasm, is most prevalent in teenagers and adults and current treatment approaches have reached a survival plateau and attempts to improve osteosarcoma prognosis have proven unsuccessful. Thus there is clear evidence that development of new agents with high efficacy and fewer side effects to provide better prognostic outcome is urgently needed. METHODS: The toxicity, function and mechanism of lycorine (LY) on osteosarcoma were accessed in vitro by CCK-8 assay, flow cytometry, and western blotting and in vivo by the xenograft osteosarcoma mouse model. RESULTS: In this study, we found that LY exhibited dose-dependent and time-dependent cytotoxic effects on human osteosarcoma cell-lines SJSA-1 and U2OS, inducing G1 phase cell cycle arrest and cellular death via apoptosis. Mechanistically, LY treatment elevated ROS generation that activates the p38 mitogen-activated protein kinases (MAPKs) and p53-dependent apoptotic program. Inhibition of ROS generation by NAC or p38 MAPK signaling by SB203580 attenuated the p53-mediated cell cycle arrest and apoptosis induced by LY. In vivo administration of LY markedly reduced tumor growth with little organ-related toxicity in a mouse xenograft model of osteosarcoma. CONCLUSION: Collectively, our data suggests that LY exhibit therapeutic potential for the treatment of osteosarcoma. LEVEL OF EVIDENCE: N/A.

The PPAR-γ antagonist T007 inhibits RANKL-induced osteoclastogenesis and counteracts OVX-induced bone loss in mice.

BACKGROUND: Osteoclasts are key determinant cellular components implicated in the development and progression of disorders driven by bone damage. Herein, we studied the upshot of T007, an antagonist of peroxisome proliferator-activated receptor-gamma (PPARγ), on osteoclastogenesis using cell and animal models. RESULTS: The in vitro assays revealed that T007 hindered the osteoclastogenesis caused by the treatment with the receptor activator of nuclear factor-κB ligand (RANKL) through inhibiting the levels of PPARγ in cells. The PPARγ siRNA partially reproduced the inhibitory action of T007. The opposite findings were produced after PPARγ overexpression. Furthermore, T007 prevented from bone loss in a mouse model of osteoporosis induced by ovariectomy (OVX). These findings implied that T007 is a potential efficient drug for the prophylaxis and cure of osteoclast-related disorders. CONCLUSIONS: Taken together, our findings demonstrated that T007 impedes osteoclastogenesis and will be useful for the therapy of bone related diseases, essentially osteoporosis.

The GLP-1 agonist, liraglutide, ameliorates inflammation through the activation of the PKA/CREB pathway in a rat model of knee osteoarthritis.

BACKGROUND: Inflammation is a common pathological phenomenon of osteoarthritis (OA). Accumulated evidence indicates that ameliorating or suppressing inflammation might be a promising and effective therapeutic strategy for the treatment of OA. Notably, glucagon-like peptide-1 (GLP-1)-based drugs are being successfully used to control glucose levels in patients with diabetes mellitus. In addition, recent findings have indicated that GLP-1 agonists, such as liraglutide have therapeutic potential in preventing inflammation-related disorders through the regulation of protein kinase A (PKA)/ cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB) signals. Intra-articular injection of monoiodoacetate (MIA) has been widely used to induce OA. Thus, the present study aimed to investigate whether liraglutide has anti-inflammatory effects on MIA-induced OA rats and uncover its underlying molecular mechanisms. METHODS: Intra-articular injection of MIA was used to induce knee OA in a rat model. Subcutaneous injection of liraglutide was used to upregulate the expression of GLP-1 receptor (GLP-1R). Western blot analysis was utilized to measure the expression of GLP-1R, PKA/CREB pathway components and inflammation-related proteins, such as tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1ß), and IL-6. Immunoprecipitation techniques were used to detect the interactions between GLP-1R and the PKA/CREB pathway. RESULTS: The levels of GLP-1R decreased significantly in the knees of OA rats, accompanied by the downregulation of PKA /CREB signals and upregulation of inflammation-related proteins. We also found that GLP-1R interacted with the PKA/CREB pathway and that liraglutide could activate PKA/CREB signals, thereby inhibiting the expression of inflammation-related proteins. CONCLUSIONS: Together our results suggest that liraglutide exhibits anti-inflammatory activity through the activation of the PKA/CREB pathway in an OA rat model.

The Novel p38 Inhibitor, Pamapimod, Inhibits Osteoclastogenesis and Counteracts Estrogen-Dependent Bone Loss in Mice.

Pamapimod (PAM) is a novel selective p38 mitogen-activated protein (MAP) kinase inhibitor proved to be effective in rheumatoid arthritis in phase 2 clinical trial. However, its effect on osteoclast-associated osteoporosis and the underlying mechanisms remain unclear. In this study, we showed that PAM suppressed receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast formation via inhibition of p38 phosphorylation and subsequent c-Fos and nuclear factor of activated T cells c1 (NFATc1) expression. In addition, the downregulated NFATc1 leads to reduced expression of its targeting gene disintegrin and metalloproteinase domain-containing protein 12 (ADAM12), which was further proven to be critical for osteoclastic bone resorption. Therefore, we treated ovariectomized (OVX) mice with PAM and revealed a protective effect of PAM on osteoporosis in vivo. In conclusion, our results demonstrated PAM can prevent OVX-induced bone loss through suppression of p38/NFATc1-induced osteoclast formation and NFATc1/ADAM12-associated bone resorption. © 2018 American Society for Bone and Mineral Research.

Spontaneous epidural hematoma of thoracic spine presenting as Brown-Séquard syndrome: report of a case with review of the literature.

BACKGROUND: Spontaneous spinal epidural hematoma (SSEH) is an uncommon clinical entity. It produces a severe neurological deficit and prompt decompression is usually the first choice of treatment. Brown-Séquard syndrome is commonly seen in the setting of spinal trauma or an extramedullary spinal neoplasm, but rarely caused by SSEH. METHODS: Case report and literature review. FINDINGS: A previously healthy man presented with Brown-Séquard syndrome below T5-T6 cord segment secondary to spontaneous epidural hematoma. He opted for conservative treatment, which was followed by rapid resolution. CONCLUSIONS: Although Brown-Séquard syndrome as a presenting feature of SSEH is rare, it does exist in exceptional case, which should be taken into consideration for differential diagnosis. Prompt surgical decompression is an absolute surgical indication widely accepted for patient with progressive neurological deficit. However, SSEH presenting with incomplete neurological insult such as Brown-Séquard syndrome might have a benign course. Successful non-operative management of this problem does not make it a standard of care, and surgical decompression remains the standard treatment for SSEH.

[Enhancement effect of caffeine on chemotherapy of osteosarcoma in Fischer 344/N rats].

OBJECTIVE: To determine the enhancement effects of caffeine on chemotherapy of transplanted osteosarcoma in Fischer 344/N rats. METHODS: Osteosarcoma-bearing Fischer 344/N rats were treated with cisplatin 2.5 mg/kg (Group DDP), caffeine 90 mg/kg x 2 d (Group caffeine), and cisplatin 2.5 mg/kg plus caffeine 90 mg/kg x 2 d (Group DDP+caffeine), and the control group was treated with normal saline in the same volume. All drugs were given by intra-peritoneum injection with micro-pump, in the rate of 0.5 ml/h. The tumor volume was measured and evaluated. The tumors were stained in TUNEL, and PCNA was detected with immunohistochemistry. The tumor growth inhibition rate, PCNA index and apoptosis index were calculated, and the survival time were recorded. RESULTS: The tumor inhibition rate was -0.5219 +/-0.1429 in control group, 0.0362 +/-0.0957 in Group DDP, -0.4193 +/-0.1345 in Group caffeine, and 0.3646 +/-0.1313 in Group DDP+caffeine (P <0.01). PCNA index was 0.4587 +/-0.1312 in control group, 0.1847+/-0.0535 in Group DDP, 0.4381 +/-0.0706 in Group caffeine, and 0.0314 +/-0.0231 in Group DDP+caffeine (P <0.01). Apoptosis index was 0.0008 +/-0.0005 in control group, 0.0077 +/-0.0060 in Group DDP, 0.0011 +/-0.0003 in Group caffeine, and 0.0295 +/-0.0069 in Group DDP+caffeine (P <0.01). And the survival time was (33.63 +/-4.63)d in control group, (52.13 +/-11.74)d in Group DDP, (35.63 +/-5.15)d in Group caffeine, and (55.13 +/-16.23)d in Group DDP+caffeine (P <0.01). CONCLUSION: Caffeine could enhance the anti-tumor effect of cisplatin in rat osteosarcoma.

[Cytotoxic effect of thermo-chemotherapy with cisplatin on osteosarcoma OS-732 cell line].

OBJECTIVE: To observe the cytotoxic effect of thermo-chemotherapy with cisplatin on osteosarcoma OS-732 cell line and to explore its mechanism. METHODS: The osteosarcoma OS-732 cell line was treated with different temperature, cisplatin alone and 43 degrees C +cisplatin for 1 h, respectively and the in vitro cytotoxic effect was observed with MTT assay. The cell cycle and the apoptotic rate were analyzed with flow cytometry (FCM); the cellular apoptosis was observed also with electron microscope. RESULT: The cytotoxicity index increase markedly as the temperature elevated or the concentration of cisplatin increased. While treated with 43 degrees C hyperthermia and cisplatin simultaneously, the cytotoxicity index increased to 72.37%;the cell cycle of the treated OS-732 cells line was changed with marked increase in S phase and decreasing in G(2)/M phase. The apoptotic rate increased markedly with the highest of 56.47%. Electron microscope showed the characteristic apoptotic alterations. CONCLUSION: Hyperthermia with cisplatin enhance cytotoxicity on osteosarcoma OS-732 cell line and the induced cell apoptosis may be one of the mechanisms of enhanced cytotoxicity by thermo-chemotherapy.

[Anterior instrumentation for the treatment of tuberculotic spinal deformity].

OBJECTIVES: To summarize the clinical results in the treatment of spinal tuberculosis with debridement, bone grafting and anterior fixation and to evaluate the safety and the value of this procedure. METHODS: From June 1997 to May 2001, 18 patients with spinal tuberculosis were treated using anterior debridement, autograft of bone and primary internal instrumentation. They were 8 men and 10 women, aged from 25 to 59 years (mean 41 years). The degree of kyphosis before surgery was 27.0 degrees to 75.5 degrees (mean 47.5 degrees +/- 11.4 degrees ). The involved spines included cervical spine (1 patient), thoracic spine (10), thoracic-lumbar spine (2), and lumbar spine (5). Average 2.8 intervertebral bodies in each patient were afflicted with tuberculosis disease. Spinal fusions were done with iliac bone grafts. RESULTS: All patients were followed up for an average of 25 months. No deep wound infection and sinus were observed after surgery. The grafted bones were fused in all patients with an average time of 3.6 months. The degree of spine kyphosis correction was 32.7 degrees +/- 8.3 degrees, and 3.2 degrees +/- 2.8 degrees was lost on average in the late stage. CONCLUSION: Anterior instrumentation for spinal tuberculosis could stabilize the spine, correct kyphosis and fuse the grafted bone.